雌激素及雌激素受体与卵母细胞成熟的关系

Impact of estradiol and its receptor-β on oocyte maturation

目的探讨促排卵患者外周血和卵泡液中雌二醇(E_2)及卵丘细胞中雌激素β受体(ER-β)与卵母细胞成熟的关系。方法选择34例行卵胞浆内单精子注射(ICSI)的患者,收集取卵日外周血、卵泡液及卵丘细胞,电化学发光法(ECLIA)检测血清及卵泡液中E_2的水平,采用实时荧光定量聚合酶链反应(Realtime-PCR)检测卵丘细胞ER-βmRNA的表达量,并记录卵母细胞成熟度。结果外周血E_2水平显著低于卵泡液内E_2的水平,两者差异有统计学意义(P=0.000),外周血E_2水平/获卵数与每位患者卵泡液中E_2平均水平呈正相关(P=0.002);MⅡ期卵母细胞内卵泡液E_2水平显著高于MⅠ期和GV期,差异有统计学意义(P<0.01);MⅡ期卵母细胞的卵丘细胞中ER-βmRNA的相对表达量是MⅠ期的2.34倍(P<0.01),是GV期的3.78倍(P<0.01)。结论外周血E_2水平间接反映卵泡液内E_2水平,卵泡液内E_2水平与卵母细胞成熟度呈正相关,卵丘细胞ER-βmRNA表达量与卵母细胞成熟呈正相关性。

Objective： To explore the estradiol（E2 ）levels in serum and follicular fluid and estradiol receptor-β （ER-β）expression in cumulus cells of ovary,and analyze the impact of E2 and ER-β on oocyte maturation of patients in stimulated cycles. Methods： A total of 34 patients who received intracytoplasmic sperm injection（ICSI）were enrolled in this study, The samples of blood, follicular fluid and cumulus cells were obtained on the day of oocyte pick- up（OPU）. Electro-chemiluminesence immunoassay（ECLIA） was used to measure E2 levels in serum and follicular fluid. ER-β mRNA in cumulus cells was measured by real-time PCR. The data of oocytes maturation were recorded, Results： The E2 levels in serum（15.31±7.23 nmol/L）were significantly lower than that in follicular fluid（3,349.24 ± 1,547.33 nmol/L）. The ratio of serum E2 levels to number of oocytes retrieved was positively correlated with the E2 levels in follicular fluid （r = 0. 214, P = 0. 002）. The E2 levels in the follicular fluid of MII oocytes （4,586.62 ± 161.61nmol/L） were significantly higher than those in the follicular fluid of M I （ 3,642.92 ± 256.55 nmol/L） and GV oocytes （3,130.99 ± 235.83nmol/L） （P〈0.01） . ER-13 mRNA expression in cumulus cells from MII oocytes （1. 000 ± 0. 521） was significantly higher than that in cumulus cells from M I （0. 426 ± 0. 204,2.34-fold） and GV oocytes （0. 264 ± 0. 137,3.78-fold） （P〈0.01）. Conclusions： The E2levels in serum indirectly reflect the E2 levels in follicular fluid. Both E2 levels infollicular fluid and ER-β expression in cumulus cells are positively correlated with oocyte maturation. The ratio of the serum E2 levels to number of oocytes retrieved could be used as a diagnostic indicator of oocyte maturation.